Valor was laid down on 27 May 1941 at Rockland, Maine by the Snow Shipyards, Inc.; launched on 8 November 1941; co-sponsored by Misses Jane and Noreen Brannan; and placed in service on 24 March 1942 at the Boston Navy Yard.

Although records are sketchy and inconclusive, the coastal minesweeper appears to have operated in the waters of the 1st Naval District, primarily out of Boston, throughout her brief career.

Late that day, she was patrolling the southern approaches to the Cape Cod Canal, alert to the possible presence of enemy intruders on this highly traveled coastal route.

Minutes before 22:00, as she patrolled north of Cuttyhunk Island in Buzzards Bay, Valor was struck by USS Richard W. Suesens.

The destroyer escort rescued seven survivors; but, although five other vessels joined in the search which continued until sunrise, the seven remaining men on board were never found.